Java日期转换使用Joda-Time工具

川长思鸟来 2022-05-30 02:20 114阅读 0赞

### 使用SimpleDateFormat来实现格式化日期 ###

import java.text.SimpleDateFormat;
    import java.util.Date;
    
    public class DateFormatExample {
    
        public static void main(String args[]) {
    
            Date today = new Date();
    
            System.out.println("今天 is : " + today);
    
            SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("dd-MM-yyyy");
            String date = DATE_FORMAT.format(today);
            System.out.println("今天 in dd-MM-yyyy format : " + date);
    
            DATE_FORMAT = new SimpleDateFormat("dd/MM/yy");
            date = DATE_FORMAT.format(today);
            System.out.println("今天 in dd/MM/yy pattern : " + date);
    
            //formatting Date with time information
            DATE_FORMAT = new SimpleDateFormat("dd-MM-yy:HH:mm:SS");
            date = DATE_FORMAT.format(today);
            System.out.println("今天 in dd-MM-yy:HH:mm:SS : " + date);
    
            //SimpleDateFormat example - Date with timezone information
            DATE_FORMAT = new SimpleDateFormat("dd-MM-yy:HH:mm:SS Z");
            date = DATE_FORMAT.format(today);
            System.out.println("今天 in dd-MM-yy:HH:mm:SSZ : " + date);
    
        }
    
    }

但是

DateFormat 的所有实现，包括 SimpleDateFormat 都不是线程安全的，因此你不应该在多线程序中使用，除非是在对外线程安全的环境中使用，如 将 SimpleDateFormat 限制在 ThreadLocal 中。如果你不这么做，在解析或者格式化日期的时候，可能会获取到一个不正确的结果。因此，从日期、时间处理的所有实践来说，我强力推荐使用joda-time 库。

### Joda-Time工具 ###

主要的特点包括：  
  
**1. 易于使用:**Calendar让获取"正常的"的日期变得很困难，使它没办法提供简单的方法，而Joda-Time能够 直接进行访问域并且索引值1就是代表January。  
**2. 易于扩展：**JDK支持多日历系统是通过Calendar的子类来实现，这样就显示的非常笨重而且事实 上要实现其它日历系统是很困难的。Joda-Time支持多日历系统是通过基于Chronology类的插件体系来实现。

**3. 提供一组完整的功能：**它打算提供 所有关系到date-time计算的功能．Joda-Time当前支持8种日历系统，而且在将来还会继续添加，有着比JDK Calendar更好的整体性能等等。

封装joda-time的时间工具类：

import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.util.Date;
    import java.util.HashMap;
    import java.util.Map;
    import java.util.TimeZone;
    
    import org.joda.time.DateTime;
    import org.joda.time.DateTimeConstants;
    import org.joda.time.DateTimeZone;
    import org.joda.time.Days;
    import org.joda.time.LocalDate;
    
    import com.sun.istack.internal.Nullable;
    
    /**
     * 使用joda的时间工具类
     * @author soyoungboy
     *
     */
    public class DateUtils {
    
        public static final long SECOND = 1000; // 1秒 java已毫秒为单位
    
        public static final long MINUTE = SECOND * 60; // 一分钟
    
        public static final long HOUR = MINUTE * 60; // 一小时
    
        public static final long DAY = HOUR * 24; // 一天
    
        public static final long WEEK = DAY * 7; // 一周
    
        public static final long YEAR = DAY * 365; // 一年
    
        public static final String FORMAT_TIME = "yyyy-MM-dd HH:mm:ss"; // 默认时间格式
    
        public static final String FORMAT_TIME_MINUTE = "yyyy-MM-dd HH:mm"; // 默认时间格式
    
        public static final String FORTER_DATE = "yyyy-MM-dd"; // 默认日期格式
    
        private static final Map<Integer, String> WEEK_DAY = new HashMap<Integer, String>();
        static {
            WEEK_DAY.put(7, "星期六");
            WEEK_DAY.put(1, "星期天");
            WEEK_DAY.put(2, "星期一");
            WEEK_DAY.put(3, "星期二");
            WEEK_DAY.put(4, "星期三");
            WEEK_DAY.put(5, "星期四");
            WEEK_DAY.put(6, "星期五");
        }
    
        /**
         * 获取当前系统时间
         * 
         * @return yyyy-MM-dd HH:mm:ss
         */
        public static String getCurrentTime() {
            DateTime dt = new DateTime();
            String time = dt.toString(FORMAT_TIME);
            return time;
        }
    
        /**
         * 获取系统当前时间按照指定格式返回
         * 
         * @param pattern
         *            yyyy/MM/dd hh:mm:a
         * @return
         */
        public static String getCurrentTimePattern(String pattern) {
            DateTime dt = new DateTime();
            String time = dt.toString(pattern);
            return time;
        }
    
        /**
         * 获取当前日期
         * 
         * @return
         */
        public static String getCurrentDate() {
            DateTime dt = new DateTime();
            String date = dt.toString(FORTER_DATE);
            return date;
        }
    
        /**
         * 获取当前日期按照指定格式
         * 
         * @param pattern
         * @return
         */
        public static String getCurrentDatePattern(String pattern) {
            DateTime dt = new DateTime();
            String date = dt.toString(pattern);
            return date;
        }
    
        /**
         * 按照时区转换时间
         * 
         * @param date
         * @param timeZone
         *            时区
         * @param parrten
         * @return
         */
        @Nullable
        public static String format(Date date, TimeZone timeZone, String parrten) {
            if (date == null) {
                return null;
            }
            SimpleDateFormat sdf = new SimpleDateFormat(parrten);
            sdf.setTimeZone(timeZone);
            return sdf.format(date);
        }
    
        /**
         * 获取指定时间
         * 
         * @param year
         *            年
         * @param month
         *            月
         * @param day
         *            天
         * @param hour
         *            小时
         * @param minute
         *            分钟
         * @param seconds
         *            秒
         * @return yyyy-MM-dd HH:mm:ss
         */
        public static String getPointTime(Integer year, Integer month, Integer day, Integer hour, Integer minute,
                Integer seconds) {
            DateTime dt = new DateTime(year, month, day, hour, minute, seconds);
            String date = dt.toString(FORMAT_TIME);
            return date;
        }
    
        /**
         * 
         * @param year
         *            年
         * @param month
         *            月
         * @param day
         *            天
         * @param hour
         *            小时
         * @param minute
         *            分钟
         * @param seconds
         *            秒
         * @param parrten
         *            自定义格式
         * @return parrten
         */
        public static String getPointTimePattern(Integer year, Integer month, Integer day, Integer hour, Integer minute,
                Integer seconds, String parrten) {
            DateTime dt = new DateTime(year, month, day, hour, minute, seconds);
            String date = dt.toString(parrten);
            return date;
        }
    
        /**
         * 获取指定日期
         * 
         * @param year
         * @param month
         * @param day
         * @return
         */
        public static String getPointDate(Integer year, Integer month, Integer day) {
            LocalDate dt = new LocalDate(year, month, day);
            String date = dt.toString(FORTER_DATE);
            return date;
        }
    
        /**
         * 获取指定日期 返回指定格式
         * 
         * @param year
         * @param month
         * @param day
         * @param parrten
         * @return
         */
        public static String getPointDatParrten(Integer year, Integer month, Integer day, String parrten) {
            LocalDate dt = new LocalDate(year, month, day);
            String date = dt.toString(parrten);
            return date;
        }
    
        /**
         * 获取当前是一周星期几
         * 
         * @return
         */
        public static String getWeek() {
            DateTime dts = new DateTime();
            String week = null;
            switch (dts.getDayOfWeek()) {
            case DateTimeConstants.SUNDAY:
                week = "星期日";
                break;
    
            case DateTimeConstants.MONDAY:
                week = "星期一";
                break;
    
            case DateTimeConstants.TUESDAY:
                week = "星期二";
                break;
            case DateTimeConstants.WEDNESDAY:
                week = "星期三";
                break;
            case DateTimeConstants.THURSDAY:
                week = "星期四";
                break;
            case DateTimeConstants.FRIDAY:
                week = "星期五";
                break;
            case DateTimeConstants.SATURDAY:
                week = "星期六";
            default:
                break;
            }
            return week;
        }
    
        /**
         * 获取指定时间是一周的星期几
         * 
         * @param year
         * @param month
         * @param day
         * @return
         */
        public static String getWeekPoint(Integer year, Integer month, Integer day) {
            LocalDate dts = new LocalDate(year, month, day);
            String week = null;
            switch (dts.getDayOfWeek()) {
            case DateTimeConstants.SUNDAY:
                week = "星期日";
                break;
            case DateTimeConstants.MONDAY:
                week = "星期一";
                break;
            case DateTimeConstants.TUESDAY:
                week = "星期二";
                break;
            case DateTimeConstants.WEDNESDAY:
                week = "星期三";
                break;
            case DateTimeConstants.THURSDAY:
                week = "星期四";
                break;
            case DateTimeConstants.FRIDAY:
                week = "星期五";
                break;
            case DateTimeConstants.SATURDAY:
                week = "星期六";
                break;
    
            default:
                break;
            }
            return week;
        }
    
        /**
         * 格式化日期
         * 
         * @param date
         * @return yyyy-MM-dd HH:mm:ss
         */
        @Nullable
        public static String format(Date date) {
            if (date == null) {
                return null;
            }
            SimpleDateFormat format = new SimpleDateFormat(FORMAT_TIME);
            return format.format(date);
        }
    
        /**
         * 格式化日期字符串
         * 
         * @param date
         *            日期
         * @param pattern
         *            日期格式
         * @return
         */
        @Nullable
        public static String format(Date date, String pattern) {
            if (date == null) {
                return null;
            }
            SimpleDateFormat format = new SimpleDateFormat(pattern);
            return format.format(date);
        }
    
        /**
         * 解析日期
         * 
         * @param date
         *            日期字符串
         * @param pattern
         *            日期格式
         * @return
         */
        @Nullable
        public static Date parse(String date, String pattern) {
            if (date == null) {
                return null;
            }
            Date resultDate = null;
            try {
                resultDate = new SimpleDateFormat(pattern).parse(date);
            } catch (ParseException e) {
    
            }
            return resultDate;
        }
    
        /**
         * 解析日期yyyy-MM-dd HH:mm:ss
         * 
         * @param date
         *            日期字符串
         * @return
         */
        @Nullable
        public static Date parse(String date) {
            if (date == null) {
                return null;
            }
    
            try {
                return new SimpleDateFormat(FORMAT_TIME).parse(date);
            } catch (ParseException e) {
                return null;
            }
        }
    
        /**
         * 解析日期 yyyy-MM-dd HH:mm:ss
         * 
         * @param timestamp
         * @return
         */
        public static String format(Long timestamp, String pattern) {
            String dateStr = "";
            if (null == timestamp || timestamp.longValue() < 0) {
                return dateStr;
            }
            try {
                Date date = new Date(timestamp);
                SimpleDateFormat format = new SimpleDateFormat(pattern);
                dateStr = format.format(date);
            } catch (Exception e) {
                // ignore
            }
    
            return dateStr;
        }
    
        /**
         * 解析日期 yyyy-MM-dd HH:mm:ss
         * 
         * @param timestamp
         * @return
         */
        public static String format(Long timestamp) {
            String dateStr = "";
            if (null == timestamp || timestamp.longValue() < 0) {
                return dateStr;
            }
            try {
                Date date = new Date(timestamp);
                SimpleDateFormat format = new SimpleDateFormat(FORMAT_TIME);
                dateStr = format.format(date);
            } catch (Exception e) {
                // ignore
            }
    
            return dateStr;
        }
    
        /**
         * 获取当前时间前几天时间,按指定格式返回
         * 
         * @param days
         * @return
         */
        public static String forwardDay(Integer days, String format) {
            DateTime dt = new DateTime();
            DateTime y = dt.minusDays(days);
            return y.toString(format);
        }
    
        /**
         * 获取当前时间前几天时间
         * 
         * @param days
         * @return
         */
        public static Date forwardDay(Integer days) {
            DateTime dt = new DateTime();
            DateTime y = dt.minusDays(days);
            return y.toDate();
        }
    
        /**
         * 获取指定时间之后或者之前的某一天00:00:00 默认返回当天
         * 
         * @param days
         * @return
         */
        public static Date day00(Integer days, String date, String zimeZone) throws Throwable {
            DateTime dt;
            TimeZone timeZone;
            try {
                if (isBlank(zimeZone)) {
                    timeZone = TimeZone.getDefault();
                } else {
                    timeZone = TimeZone.getTimeZone(zimeZone);
                }
                if (isBlank(date)) {
                    dt = new DateTime().withZone(DateTimeZone.forTimeZone(timeZone)).toLocalDateTime().toDateTime();
                } else {
                    dt = new DateTime(date).withZone(DateTimeZone.forTimeZone(timeZone)).toLocalDateTime().toDateTime();
                }
            } catch (Exception e) {
                throw new Throwable(e);
            }
    
            DateTime y = dt.minusDays(days).withHourOfDay(0).withMinuteOfHour(0).withSecondOfMinute(0);
            return y.toDate();
        }
    
        /**
         * 获取指定时间之后或者之前的某一天23:59:59 默认返回当天
         * 
         * @param days
         *            偏移量
         * @return
         */
        public static Date day59(Integer days, String date, String zimeZone) throws Throwable {
            DateTime dt;
            TimeZone timeZone;
            try {
                if (isBlank(zimeZone)) {
                    timeZone = TimeZone.getDefault();
                } else {
                    timeZone = TimeZone.getTimeZone(zimeZone);
                }
                if (isBlank(date)) {
    
                    dt = new DateTime().withZone(DateTimeZone.forTimeZone(timeZone)).toLocalDateTime().toDateTime();
                } else {
                    dt = new DateTime(date).withZone(DateTimeZone.forTimeZone(timeZone)).toLocalDateTime().toDateTime();
                }
            } catch (Exception e) {
                throw new Throwable(e);
            }
            DateTime y = dt.minusDays(days).withHourOfDay(23).withMinuteOfHour(59).withSecondOfMinute(59);
            return y.toDate();
        }
    
        /**
         * 计算两个时间相差多少天
         * 
         * @param startDate
         * @param endDate
         * @return
         */
        @Nullable
        public static Integer diffDay(Date startDate, Date endDate) {
            if (startDate == null || endDate == null) {
                return null;
            }
            DateTime dt1 = new DateTime(startDate);
            DateTime dt2 = new DateTime(endDate);
            int day = Days.daysBetween(dt1, dt2).getDays();
            return Math.abs(day);
        }
    
        /**
         * 获取某月之前,之后某一个月最后一天,24:59:59
         * 
         * @return
         */
        public static Date lastDay(Date date, Integer month) {
            DateTime dt1;
            if (month == null) {
                month = 0;
            }
            if (date == null) {
                dt1 = new DateTime().minusMonths(month);
            } else {
                dt1 = new DateTime(date).minusMonths(month);
            }
            DateTime lastDay = dt1.dayOfMonth().withMaximumValue().withHourOfDay(23).withMinuteOfHour(59)
                    .withSecondOfMinute(59);
            return lastDay.toDate();
        }
    
        /**
         * 获取某月月之前,之后某一个月第一天,00:00:00
         * 
         * @return
         */
        public static Date firstDay(Date date, Integer month) {
            DateTime dt1;
            if (month == null) {
                month = 0;
            }
            if (date == null) {
                dt1 = new DateTime().minusMonths(month);
            } else {
                dt1 = new DateTime(date).minusMonths(month);
            }
            DateTime lastDay = dt1.dayOfMonth().withMinimumValue().withHourOfDay(0).withMinuteOfHour(0)
                    .withSecondOfMinute(0);
            return lastDay.toDate();
        }
    
        public static Date addDay(Date date, int offset) {
            DateTime dt1;
            if (date == null) {
                dt1 = new DateTime().plusDays(offset);
                return dt1.toDate();
            }
            dt1 = new DateTime(date).plusDays(offset);
            return dt1.toDate();
    
        }
    
        /**
         * 传入日期时间与当前系统日期时间的比较, 若日期相同，则根据时分秒来返回 , 否则返回具体日期
         * 
         * @return 日期或者 xx小时前||xx分钟前||xx秒前
         */
        @Nullable
        public static String getNewUpdateDateString(Date now, Date createDate) {
            if (now == null || createDate == null) {
                return null;
            }
            Long time = (now.getTime() - createDate.getTime());
            if (time > (24 * 60 * 60 * 1000)) {
                return time / (24 * 60 * 60 * 1000) + "天前";
            } else if (time > (60 * 60 * 1000)) {
                return time / (60 * 60 * 1000) + "小时前";
            } else if (time > (60 * 1000)) {
                return time / (60 * 1000) + "分钟前";
            } else if (time >= 1000) {
                return time / 1000 + "秒前";
            }
            return "刚刚";
        }
        /**
         * 
         * @Title: isBlank
         * @Description: TODO(判断字符串是否为空或长度为0 或由空格组成)
         * @param @param str
         * @param @return 设定文件
         * @return boolean 返回类型
         * @throws
         */
        public static boolean isBlank(String str) {
            return (str == null || str.trim().length() == 0);
        }
        
        public static void main(String[] args) throws Throwable {
             System.out.println(lastDay(new Date(),2));
             System.out.println(firstDay(null,0));
             TimeZone zone1=TimeZone.getTimeZone("GMT+8");
             TimeZone zone2=TimeZone.getTimeZone("GMT-5");
             System.out.println(format(new Date(),zone1,FORMAT_TIME));
             System.out.println(format(new Date(),zone2,FORMAT_TIME));
            
             System.out.println(format(day00(0,"2017-5-11","GMT+0")));
             System.out.println(format(day00(0,"2017-5-11","GMT+8")));
             System.out.println(format(day00(0,"2017-5-11","GMT-8")));
             Date date1 =parse("2017-05-11 17:53:52");
            
             System.out.println(diffDay(date1,new Date()));
    
             DateTime dateTime = new DateTime().withDayOfWeek(1);
            
             DateTime dateTime1 = new DateTime().withDayOfWeek(7).withTime(0, 0,
             0, 0);
             System.out.println(format(dateTime.toDate()));
            
             System.out.println(format(dateTime1.toDate()));
    
            System.out.println(format(new Date(), "MM/dd"));
        }
    
    }

其中测试代码结果：

Fri Jun 30 23:59:59 GMT+08:00 2017
    Tue Aug 01 00:00:00 GMT+08:00 2017
    2017-08-28 19:47:28
    2017-08-28 06:47:28
    2017-05-10 00:00:00
    2017-05-11 00:00:00
    2017-05-10 00:00:00
    109
    2017-08-28 19:47:29
    2017-09-03 00:00:00
    08/28